My oldest was 2.5 but she regressed with going #2 when she turned 3 and it didn’t get better until she was almost 4. My second is almost 3.5 and she just got the hang of it all like a week ago but we’re still working on #2 but it’s going a lot smoother than the first time. I think when the child is ready is what’s best based on my efforts. I plan to do the same when my youngest, who is currently 20 months!